1. Field
An embodiment of the inventive concepts described herein relates to a semiconductor memory device, and more particularly, relates to an auxiliary power device and a user device that includes the same.
2. Description of the Related Art
A semiconductor memory device may be a memory device which stores data using semiconductor elements. Semiconductor memory devices may be divided into volatile memory devices such as, for example, a DRAM, an SRAM, and so on, and nonvolatile memory devices such as, for example, an EEPROM, an FRAM, a PRAM, an MRAM, a flash memory, and so on. While a volatile memory device may lose data stored therein during a loss of power, a nonvolatile memory device may retain data stored therein even during a loss of power.
In recent years, the integration of semiconductor memory devices may have been improved with development of semiconductor integration technology. Thus, the capacity of semiconductor memory devices may have increased. In particular, a flash user system may be widely used as a storage medium for a computing system by virtue of such merits as a fast programming speed, a mass storage capacity, and so on.
To improve the capacity and operating speed of the flash user system, a plurality of flash memory devices may be overlapped. In this case, the power used may exceed an allowable power of a power supply device of a host connected to a flash memory device. This may cause the power of the host and the flash memory device to become unstable. Operation of the flash memory device may be limited by the unstable power. Thus, performance of the flash user system may be overall reduced.